ZnO films have been grown on silicon (100) and sapphire (0001) substrates by pulsed laser deposition (PLD). The influences of substrate temperature and laser fluence on the properties of the films were studied. The effects of annealing on the ZnO films were investigated by X-ray photoelectron spectroscopy (XPS). The surface properties of ZnO were studied by scanning tunneling spectroscopy (STS). The band edge emission properties of the ZnO films have been studied by the photoluminescence spectroscopy (PL).